Conventional automotive hoses, such as those for delivering fuel, include an inner rubber liner which is resistant to the harsh, degrading effects of gasoline, a fiber layer surrounding the inner rubber tube, and an outer rubber tube surrounding the fiber layer. However, due in part to the recent developments in automotive technology, hoses carrying automotive fuel, such as gasoline, are frequently subject to high pressures and high temperatures. When gasoline is subjected to such conditions it tends to oxidize and develop peroxides that can potentially deteriorate the rubber liners. Such deterioration of the fuel line is likely to result in cracking or fuel leakage. Consequently, a need has arisen for hoses which are more resistant to these harsh temperature and chemical conditions.
Attempts have recently been made to overcome the deficiencies exhibited by fuel hoses made of rubber and other polymers. For example, fuel hoses comprising a fluoropolymer inner layer and a braided fiberglass outer layer have been proposed. Hoses of this type typically include a polytetrafluoroethylene (PTFE) liner having a wall thickness of about 25-35 mils. PTFE liners of this thickness are extraordinarily temperature and chemical resistant, but tend to be expensive and often kink and deform during manufacturing, packaging and use. This kinking can produce deformation and sometimes undetectable defects in the tubing which could cause the hose to fail in service and release fuel vapors or liquid fuel with obvious life-threatening consequences.
Accordingly, there is a need for a kink-resistant hose for safely delivering liquids, such as fuel and coolant. The hose should be cost effective, chemical-resistant, and have the ability to resist high temperatures.